At midday, clouds were seen starting to roll in around the San Bernardino Mountains, and it was windy and very chilly.
Forecasters say the storm could bring snow at the 3,000-foot level at the intersection of the 138 and 15 freeways.
Snow plows and other vehicles are on standby at the Caltrans station in the Cajon Pass. Caltrans says they will be operating 24-7, working on 12-hour shifts. They've hired all their winter help, which means they doubled the number of crews that are on standby.
At 7 p.m., they are expecting to activate what they call Summit Comm, which is their operation center working in conjunction with the California Highway Patrol. They will keep a very close eye on the Cajon Pass because as drivers who commute up and down the 15 Freeway know very well, it can become difficult to drive during a strong winter storm.
"It was pretty scary. I mean, the visibility was pretty low. I definitely wouldn't recommend it," said Alex Serna of Highland.
Drivers were urged to plan ahead because the 15 Freeway in the Cajon Pass could be covered with a layer of snow. The ski resorts are also expecting a lot of snow from the storm, so if you're headed to the mountains, bring your chains with you.
On Thursday, metro L.A. and O.C. can expect about half an inch of rain with temps in the low 60s, and the valleys and I.E. will get up to an inch with temps in the high 50s. The high desert will get rain in the a.m., along with gusts and temps in the low 50s.